JPH0423926B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to sandbags filled with granules obtained by mixing and press-molding a water-insoluble water-absorbing resin and a fibrous material, and a method for using the same.

[Conventional technology]

Generally, sandbags are used as an emergency measure to prevent disasters such as the failure or overflow of river embankments due to floods, the intrusion of inflowing sediment, and the collapse of embankments and slopes due to rainwater. A bag of sufficient strength and size is manually filled with earth and sand (mainly sand), and the bag is closed by tightly tying the inlet.

Conventional sandbags are constructed as described above, and during normal times, only the bags are prepared, and when a disaster such as the one described above is expected to occur or occurs, the bags are dispatched to the disaster area and are used to prevent damage to the disaster area. Under poor weather conditions, bags are filled with sand, the input port is closed, and the sandbags are piled up.

[Problem that the invention seeks to solve]

With the conventional sandbags mentioned above, the bag is manually filled with soil and the input port is closed under the poor conditions of the disaster area, and the bag is formed into a sandbag. There was a problem in that it was difficult to make a large amount of sandbags in a short period of time in a disaster area.

[Means for solving problems]

The sandbag according to the first invention is a bag made of a water-permeable material and filled with granules obtained by mixing a water-insoluble water-absorbing resin and a fibrous material and press-molding the mixture.

The method of using sandbags according to the second invention is to combine a sandbag made of a water-permeable material and filled with granules made by mixing and press-molding a water-insoluble water-absorbent resin and a fibrous material with a heavy sandbag. This is a method of forming a sandbag layer.

[Effect]

In the sandbag according to the first invention, a bag made of a water-permeable material is filled with a water-insoluble water-absorbing resin, and this water-insoluble water-absorbing resin absorbs water hundreds to thousands of times its own weight and turns it into a water gel. Therefore, sandbags can be easily formed by water supply. Moreover, since the water-insoluble water-absorbing resin is mixed with a fibrous material and formed into granules by pressure molding, a water-absorbing gel layer is not formed only on the surface of the water-insoluble water-absorbing resin when it becomes a water-absorbing gel. It is possible to form sandbags that fully utilize the water absorption ability of the water absorbent resin. In other words, when a powdered water-insoluble water-absorbing resin is used alone, it is difficult to fill the bag, and not only does it flow out from the water passage holes drilled in the bag, but the powdered resin also generates static electricity. Because it was easily contaminated, it aggregated into aggregates, and the resin at the center of the aggregates was unable to absorb water sufficiently.

In the present invention, since the granules are formed by mixing a water-insoluble water-absorbing resin and a fibrous material and forming the mixture under pressure, it can be easily filled into a bag and does not leak out from the holes for water passage. Furthermore, since the granules are a pressure-molded product of fibrous material and resin, water enters the gap between the fibrous material and resin, and further penetrates into the interior due to capillary action, fully demonstrating the water absorption ability of the resin. It will be necessary to do so. In addition, in the case of mixtures and pressure molding of fibrous material made of bundles of fine fibers such as natural fibers, the fibrous material swells with water, so the pressure molded granules gradually break down as they swell. , effectively suppressing agglomeration.

Further, in the method of using the sandbag according to the second invention, since the sandbag according to the first invention is combined with a heavy sandbag to form a sandbag layer, the weight of the entire sandbag layer becomes large and the sandbag layer becomes strong. The sandbag of the first invention can be formed into a sandbag layer even in water.

〔Example〕

The first invention is a sandbag in which a water-permeable bag is filled with granules obtained by mixing and press-molding a water-insoluble water-absorbent resin and a fibrous material. The water-insoluble water-absorbing resin of the first invention comprises a copolymer of a monomer (A) and a polysaccharide (B), a polymer of a monomer (A) and a crosslinking agent (C), and a copolymer of a monomer (A) and a crosslinking agent (C). It is a polymer obtained by polymerizing a polymer (A), a polysaccharide (B), and a crosslinking agent (C) as essential components, and hydrolyzing it if necessary. The monomer (A) may be a monomer that is hydrophilic or has become hydrophilic through hydrolysis, or a monomer that is water-soluble or has become water-soluble through hydrolysis, either alone or in combination. It is what you use.

Examples of the polymer of monomer (A) and polysaccharide (B) include hydrolysates of starch-acrylonitrile graft copolymers, cellulose-acrylic acid graft copolymers, and salts thereof.

In addition, as a polymer of monomer (A) and crosslinking agent (C),
For example, polyacrylamide crosslinked with a divinyl compound (methylenebisacrylamide etc.) and its partial hydrolyzate, crosslinked poval, JP-A-52
Examples include saponified cross-linked vinyl ester-unsaturated carboxylic acid copolymers, cross-linked polyethylene oxide, etc., as described in No. 14689 and JP-A No. 52-27455.

Furthermore, as a polymer obtained by polymerizing monomer (A), polysaccharide (B), and crosslinking agent (C) as essential components and hydrolyzing if necessary, for example, Japanese Patent Publication No. 53-46199, Japanese Patent Publication No. 53 −46200 Publication and Special Publication No. 1983−
Examples include a crosslinked starch-acrylamide graft copolymer, a crosslinked starch-acrylic acid graft copolymer, and salts thereof, which are described in Japanese Patent No. 4462.

Two or more of these hydrophilic polymers may be used in combination, and the particle size of the polymer particles is usually 5 to 5,000 μm or less, preferably 20 to 500 μm, and usually has a water absorption capacity of 60 ml/g or more.

The fibrous material mixed with water-insoluble water-absorbing resin and press-molded is natural fiber (vegetable fibers include cellulose, such as paper, cotton, straw, sawdust, grass charcoal, pulp, etc.; animal fibers include silk). , wool, etc.), man-made fibers (cellulose-based materials such as rayon, acetate, etc.), organic fibers such as synthetic fibers (polyamide, polyester, acrylic, etc.), inorganic fibers such as asbestos, perlite, and combinations of two or more of these. The system can be mentioned. Among these, preferred are fibers or vegetable fibrous substances that can become fibrous in water (hereinafter organic fibrous substances are simply referred to as fibers), such as paper,
These include crushed paper, cotton, pulp, and grass charcoal. Among these, pulverized paper is particularly preferred, and pulverized paper containing small pieces of unpulverized paper (for example, about 1 to 50 mm) can also be used. In addition to the pulverized paper, other fibers can also be used in combination. The ratio of pulverized paper to other fibers is usually 100:0 to 1:99, preferably 100:0 to 50:50.

The fibers can be in powder form, such as fine powder or ground fibers, and fibers, such as cut single fibers (usually less than 100 denier in thickness), or bundles of multiple fibers. Examples include those treated with a suitable sizing agent and cut, and those cut from woven fabrics, non-woven fabrics, knitted fabrics, sheets (for example, paper), and those that are loosened. The fiber length is not particularly limited, but is usually 0.01 to 50 mm, preferably 0.01 mm.
~5mm.

The mixing ratio of the water-insoluble water absorbent resin and the fibrous material is usually 5/95 to 90/10 (weight ratio), preferably
20/80 to 80/20, and the mixture of both is 0.3g/
It is press-molded to a bulk specific gravity of at least 0.7 g/cm ³ , preferably at least 0.7 g/cm ³ .

Pressure molding methods include pressure molding into pellets in a formwork at room temperature, sheet shapes,
There is a method in which the material is pressure-formed into a rod or block shape and then cut or crushed into an appropriate size. Pressure molding requires heating (e.g. 20 to 150°C) and humidification (60°C).
~100% humidity).

Pressure forming machines are roll press machines such as compacting machines with corrugated roll specifications, calendar machines, briquette machines, hydraulic half-plate presses, screw presses, etc., and the bulk specific gravity of the press-formed product is 0.3g. 1~3000Kg/ ^cm3 or more
cm ² , preferably at a pressure of 100 to 200 g/cm ² .

The shape of the pressure-molded product obtained may be arbitrary, and includes various shapes such as a sphere, a cylinder, a cube, a rectangular parallelepiped, a cone, a pyramid, a rod, a sheet, and a roll. The size is such that the shortest diameter of the press-molded product is usually 10 cm or less, preferably 3 cm or less.

On the other hand, the material of the bag used to fill the pressure-molded granules is strong enough to withstand vertical and surrounding loads even when layered as sandbags through water, and the water-insoluble water-absorbent resin absorbs water. It has the ability to absorb water and prevent water from leaking even when it becomes a gel.It can be used for 50 to 300 mesh fabrics, knitted fabrics, etc. made of materials such as natural fibers, artificial fibers, metal fibers, and mineral fibers.
Non-woven fabric etc. can be used.

It can also be used by stacking sheets of thermoplastic resin such as polyethylene or polypropylene and heat-sealing the edges to form a bag. Make holes in the bag that are small enough to prevent leakage even if the resin absorbs water and turns into a gel. The most suitable material in terms of strength is
It is a woven fabric made of slit yarn made by slitting a stretched film or sheet of thermoplastic resin such as polypropylene, and allows water to pass through it well without leaking gelled water-insoluble resin.

Bags made of these materials can have any shape, but it is convenient for construction and handling to be a single square bag or a continuous band bag. If the bottom is 25~30
cm, and the sides are preferably about 60 to 70 cm for handling purposes. Further, the amount of granules to be filled into the bag is preferably 0.1 to 5.0% by volume, preferably 0.2 to 2.0% by volume, based on the volume of the bag, in view of the amount of water retained after water-absorbing gelation. When filling a bag with granules, only the granules may be filled, but it is advantageous to mix in a predetermined proportion of an inert substance such as earth and sand to stabilize the bag when stacking it into a sandbag.

FIG. 1 is an explanatory diagram showing an embodiment of the first invention,
1 in A in the figure is a bag made of 100 mesh woven nylon shears with a bottom of 25 to 30 cm and sides of 60 to 70 cm, and filled with granules. For example, the volume of bag 1 is 25 to 45 cm. In this case, fill with 50 to 500 g of granules. In addition, 2 in B in the figure is a belt-shaped bag made by connecting the bags 1, and 3 is the distance between the bags 1, which can be arbitrarily determined depending on the method of stacking the two sandbags. C in the figure shows the state in which the belt-shaped bag 2 is rolled up and stored.

The sandbag according to the first invention is constructed as described above, and when the sandbags 1 and 2 are placed in a predetermined place with the granules in a dry state and water is supplied artificially or by rainfall, the water-insoluble water-absorbing resin is It absorbs hundreds to thousands of times its own weight in water and turns it into a gel, forming a heavy pillow-shaped sandbag. At that time, the water-insoluble water-absorbent resin is mixed with a fibrous material and formed into granules that are pressure-molded.
Even if the water-insoluble water-absorbent resin on the surface layer absorbs water and forms a gel layer, the water on the surface is guided inside by the fibrous material itself and the capillary phenomenon in the gap between the fibrous material and the resin. Since the gel layer does not interfere with subsequent water absorption and gelatinization, the water-insoluble water-absorbing resin fully exhibits its water-absorbing ability and retains a large amount of water. Furthermore, since the retained water is irreversible, even if a load is applied to the sandbag, water will not be released and the sandbag will maintain its function.

The second invention is a method for stacking sandbags according to the first invention. The sandbags 1 and 2 according to the first invention are made by drying a water-insoluble water-absorbing resin.
Or, if you stack the band-shaped sandbags 2 and supply water,
Sandbag layers can be obtained in disaster areas in a short time and with little effort. However, since the weight of sandbags 1 and 2 is obtained from water, when flowing water collides with sandbags 1 and 2 stacked on a river embankment, the layers of sandbags 1 and 2 may collapse due to pressure. Therefore, the method of the second invention uses sandbags that are heavier than the sandbags 1 and 2 of the first invention filled with earth and sand, etc.
Sandbags 1 and 2 of the first invention are combined to form a sandbag layer.

FIG. 2 is an explanatory diagram showing an embodiment of the second invention, and A in FIG. 2 shows a sandbag in which sandbags 1 are arranged on land 5 and a sandbag 6 filled with heavy earth and sand is placed on top of the sandbags 1. 8 is the running water on the side of the sandbag layer, and arrow A is the pressure from the running water 8. B in FIG. 2 shows a sandbag 6 filled with heavy earth and sand placed on the strip-shaped sandbag 2 at intervals 3.
Moreover, C in FIG. 2 shows the sandbag 1 of the first invention and the sandbag 6 filled with heavy earth and sand stacked side by side.

In this way, by combining the sandbags 1 and 2 of the first invention with the heavy sandbag 6, a heavy and strong sandbag layer is formed, and even if the running water 8 collides with it and pressure is applied, the sandbag layer will remain stable. Will not collapse,
By using the sandbag of the first invention, such a strong sandbag layer that can maintain its function as a sandbag layer can be formed in a short time and with little labor.

〔Effect of the invention〕

As explained above, the first invention is made by filling a bag made of a water-permeable material with a certain strength with granules obtained by mixing and pressure-molding a water-insoluble water-absorbing resin and a fibrous material, thereby requiring only a small amount of human effort. This method has the effect of forming a sandbag layer in a short time.

In addition, the second invention combines the sandbags of the first invention and heavy sandbags to form a sandbag layer, so even when various pressures are applied, the layered state is maintained firmly and disasters are prevented. There is an effect that can be done.

[Brief explanation of drawings]

FIGS. 1A, B, and C are explanatory diagrams of an embodiment of the first invention, and FIGS. 2A, B, and C are explanatory diagrams of an embodiment of the second invention. In the figure, 1 is a sandbag, 2 is a band-shaped sandbag,
6 is a heavy sandbag filled with earth and sand, and 8 is running water.

Claims (1)

[Scope of Claims] 1. A sandbag formed by filling a bag made of a water-permeable material with granules obtained by mixing and press-molding a water-insoluble water-absorbing resin and a fibrous material. 2. The sandbag according to claim 1, wherein the granules have a bulk specific gravity of 0.3 g/cm ³ or more. 3. The sandbag according to claim 1, which is filled with the granules in an amount of 0.2 to 2.0% by volume based on the volume of the bag. 4. A method of using the above-mentioned sandbags, in which a sandbag made of a water-permeable material is filled with granules made by mixing a water-insoluble water-absorbent resin and a fibrous material and then pressure-molded, and a heavy sandbag is combined to form a sandbag layer.